However, O'Neill insists that the club should rebuff any forthcoming offers.
"I obviously want to keep players at the football club," said O'Neill. "If there is anyone desperately unhappy and there is nothing we can do about that and something arrives in January, then I will give that some consideration.
"But the main point would be trying to stabilise things rather than letting people go. That would be my general view of things."
The Black Cats have risen to tenth in the Premier League table since O'Neill's appointment.